After the teacher's education, Xiao Ming made his learning attitude clear

After the teacher's education, Xiao Ming made his learning attitude clear

Improper use of words
Change to:
After the teacher's education, Xiao Ming (clear - changed to "correct") learning attitude

Last night, my family went to the cinema. I was the only one doing my homework at home

Last night, everyone went to the cinema. I was the only one doing my homework at home

As shown in the figure, half of the square metal block with a side length of 10cm is placed on the horizontal table with an area of 1m2. When the indication of the spring dynamometer is 10N, the pressure of the metal block on the table is 4 × 103pa, and the density of the metal block is calculated

S = 0.1M × 0.1m2 = 0.5 × 10-2m2f = PS = 4 × 103pa × 0.5 × 10-2m2 = 20 (n) the stress analysis of the metal block shows that: g = F + T = 20 + 10 = 30 (n) from g = mg = ρ VG, ρ = GVG = 30n (0.1 × 0.1 × 0.1) m3 × 10N / kg = 3 × 103kg / m3 A: the density of the metal block is 3 × 103kg / m3

1、 Fill in the blanks according to the examples
Blue () example: terraced fields
Water mist
White one roars
I. flowers
A small tree
There should be no blue Wang Wang

LAN yingying
Grey and grey
The vast expanse of white
Layers of mist, patches of mist
There was a roar, a roar
A bunch of flowers, a bunch of flowers
Little trees, little trees

Given that the domain of function f (x) is [- 1 / 2,1 / 2], find the domain of function y = f (AX) + F (x / a) (a > 1)
The answer is [- 1 / 2a, 1 / 2A]
2A is at the denominator

-1/2≤ax≤1/2
Then - 1 / 2A ≤ x ≤ 1 / 2A
-1/2≤x/a≤1/2
Then - A / 2 ≤ x ≤ A / 2
If a / 2 ＞ 1 / 2a, - 1 / 2A ＜ - 1 / 2a, then
[-1/2a,1/2a]

Cosx = 1 / 3 and - π / 2

cosx=1/3
Then: from sin & # 178; X + cos & # 178; X = 1, we can get: Sin & # 178; X = 8 / 9
Because: - π / 2

How to solve the problem of off form calculation in grade five

1）25%*132+1/4*8 2)32*0.125*25 =1/4*132+1/4*8 =(4+8)*0.125*25 =1/4*(132+8) =(4*25)*(8*0.125) =1/4*140 =100*1 =35 =1000 3)75%*76+25*4+0.75*12 =3/4*76+3/4*12+25*4 =3/4*88+100 =166 4)3200*1/8÷2/5+1270 5...

Derivation of derivative function
What is the derivative function of F (x) = A / (xlnx)? The teacher gave F & # 180; (x) = [- A (LNX + 1)] / (xlnx) &# 178
Why? I can't figure it out after several calculations

Derivative of compound function
f ﹙x ﹚＝ a /﹙xLnx )
f '﹙x ﹚＝ [a /﹙xLnx )]'
=-a(xlnx)'/(xlnx)^2
=-a(1+lnx)/(xlnx)^2

We know that a + B + C = 0, and prove that ab + BC + Ca ≤ 0

Prove: because a + B + C = 0, so (a + B + C) 2 = 0. Expand AB + BC + Ca = - A2 + B2 + C22, so AB + BC + Ca ≤ 0

How to understand the effect of "short ruler and slow clock"?
I haven't studied college physics, so it's very difficult for me to understand the principle of invariable speed of light. It's said on the Internet that when the speed of an object is close to the speed of light, its time will slow down. This is very vague. How can I understand it? How do I think the clock should be faster? Suppose a flying ship takes off from the earth at 8 o'clock at 0.8 times the speed of light, when the clock on the Earth shows 8:10, The watch on the astronaut's hand is about 8:10? I think it should be 8:10. In other words, the clock is getting faster, and the astronaut's feeling is that more than 10 minutes have passed - at this time, the typist on the spacecraft should have typed much more words than the usual 10 minutes. Is my understanding correct?

Let's take an example from a textbook. There is a pulsed laser and a receiver on the floor of a high-speed train. There is a plane mirror directly above it. Light is reflected through the plane mirror and received by the receiver. In the view of people on the train, the length of light passing up and down vertically is 2 hours. In the view of people on the ground, due to the high-speed movement of the train, the movement of light has a horizontal component, That is, in the process of light propagation, the train moves forward for s, so the actual distance of light propagation is 2 √ (H ^ 2 + (s / 2) ^ 2), which is larger than 2 h. then we accept Einstein's assumption that the speed of light is constant in any inertial frame, and it is easy to compare the same physical process. People on the train feel it for a shorter time than people on the ground, It's like the clock in the car is slowing down
In the same way, for your question, it is obvious that you are wrong. The time on board should be less than 10 minutes
For relativity, you can find a book on electrodynamics, which is more in-depth, and there is nothing very difficult in mathematics. The key is understanding